Quite a few things will cause this
>>Com Add-ins
1. Open Outlook and go to Tools, then Options.
2. Click on the "Other" tab and then click on "Advanced Options."
3. Click on the "COM Add ins" box.
4. Make note of any add-ins that are checked, then uncheck them.
5. Close outlook, kill the process in Task manager then open and close it
to see if the issue is resolved.
>>Caching mode for Exchange
1. In Outlook go to Tools, Options.
2. Click on "Mail Setup" then "Email Accounts."
3. Highlight the Exchange server and click "Change."
4. Uncheck the box labeled "User cached Exchange mode."
>>Spyware
Various spyware programs can cause this run a spyware scanner
>>Installed Applications that cause this
Citrix clients.
Spamsubtract from Intermute
Freedom Firewall by HP
Blue Tooth drivers
WinFax Software
Franklin-Cover Plan Plus!
Anti-virus/firewall programs that are set to scan incoming and outgoing mail.
And of course microsofts take
http://support.microsoft.com/default...;EN-US;q196366